Rotary filter type particulate removing device

ABSTRACT

A rotary filter type particulate removing device is provided. A rotary cylinder ( 2 ) rotates in a stationary cylinder ( 1 ) to change an exhaust gas introduced into the stationary cylinder ( 1 ) to a circulating flow so as to apply a centrifugal force on particulates in the exhaust gas in order to collect the particulates circulating in the stationary cylinder ( 1 ) into a trap ( 15 ) provided at a lower part of the particulate removing device. A filter is located on an inner wall of the rotary cylinder ( 2 ) and a huge number of punching holes ( 8 ) are formed in the lateral wall of the rotary cylinder. A fan ( 7 ) is secured on the rotary cylinder ( 2 ) which projects to the outside from the stationary cylinder ( 1 ) to constitute a sirocco fan. The exhaust gas passes through the punching holes ( 8 ) of the rotary cylinder ( 2 ) and flows into the interior of the filter. The exhaust gas further flows towards the sirocco fan. Then, the exhaust gas passes the filter again, and is discharged to the outside through the punching holes ( 8 ) of the rotary cylinder ( 2 ).

TECHNICAL FIELD

The present invention primarily relates to a device attached to anexhaust pipe of a diesel-engine vehicle to remove particulates from anexhaust gas.

BACKGROUND ART

One of currently available methods for removing particulates from anexhaust gas of a diesel-engine vehicle includes absorbing theparticulates with a filter and superheating the filter when a suitableamount of particulates is absorbed, so as to burn the particulates. Thefilter is then cleaned for reuse.

Because this conventional method uses the filter to absorb theparticulates, it inherently involves cleaning of the filter.

The present invention provides a method of removing particulates withoutabsorbing the particulates with the filter.

DISCLOSURE OF THE INVENTION

A rotary cylinder in a stationary cylinder is rotated by a motor fixedto a head cover of the stationary cylinder. An exhaust gas introducedinto the stationary cylinder becomes a circulating gas flow by means ofrotating vanes attached to the rotary cylinder. The centrifugal forcecauses the particulates to flow along an inner wall of the stationarycylinder. A lower part of the stationary cylinder has an openingextending in a longitudinal direction of the cylinder, and theparticulates collect into a lower trap via this opening.

A filter is provided along an inner wall of the rotary cylinder.

The rotary cylinder is journally supported by a bearing provided at anend cover of the stationary cylinder. A fan is secured on a projectingportion of the rotary cylinder which extends outwards from the endcover. This fan serves as a sirocco fan. An end cap of the rotarycylinder is removed in order place the filter in contact with the innerwall of the rotary cylinder.

A huge number of punching holes are formed in a wall of the rotarycylinder.

The fan rotates as the rotary cylinder rotates, and the exhaust gasflows through the punching holes of the rotary cylinder to reach theinside of the filter. The exhaust gas further flows toward the siroccofan and passes through the filter again. The exhaust gas is thendischarged to the ambient through the punching holes of the rotarycylinder.

The filter is rotating and the centrifugal force acts on theparticulates so that only a weak force acts on the particulates towardthe filter. Thus, clogging of the filter hardly occurs. At the sametime, it is possible to securely prevent those particulates which havelarger sizes than meshing of the filter from flowing into the interiorof the filter.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a rotary filter type particulateremoving device;

FIG. 2 is a cross-sectional view taken along the line I-I.

FIG. 3 is a cross-sectional view taken along the line J-J.

FIG. 4 illustrates a perspective view of a sheet filter.

BEST MODE FOR CARRYING OUT THE INVENTION

A rotary cylinder 2 rotates in a center portion of a stationary cylinder1. The rotary cylinder 2 is journally supported between a head cover 3and end cover 4 of the stationary cylinder. The rotary cylinder 2 iscoupled to a motor 5 fixed on the head cover 3 and rotated by the motor.The rotary cylinder extends beyond the end cover 4 so that it projectsoutward, and a fan 7 is secured on the projecting part of the rotarycylinder 2. The fan serves as a sirocco fan. An end cap is removablyattached to the end of the projection part of the rotary cylinder.

A huge number of punching holes 8 are formed in the entire lateral wallof the rotary cylinder 2. The filter can be placed inside the rotarycylinder from the end cap side. The filter is then disposed along theinner wall of the rotary cylinder.

Inside the stationary cylinder 1, the rotary cylinder 2 has rotary vanes10 on its outer surface. The rotary vanes 10 are fixed to the rotarycylinder and rotate together. An exhaust pipe 12 which admits an exhaustgas 11 of a vehicle has an end 13 which opens in a center area of thecylinder between the rotary vanes 10 and head cover 3.

As illustrated in FIG. 2, the rotary vanes 10 changes the exhaust gas tothe circulating flow. The particulates in the exhaust gas circulatealong the inner wall of the stationary cylinder due to the centrifugalforce, and are collected into a trap 15 via an opening formed in a lowerportion of the stationary cylinder.

In order to make the exhaust gas substantially steady circulating flow,the rotary vanes 10 may have a certain device such as wire gauze,punching plates, brushes and other light-weight devices to restrict aturbulent flow which bounds against the inner wall of the cylinder.

Referring to FIG. 3, the fan 7 rotating together with the rotarycylinder discharges the gas from the rotary cylinder to the ambient. Thefan is housed by a cover 6 so that it constitutes a sirocco fan.

The filter of this particulate removing device is designed not to absorbthe particulates. Therefore, the filter can have a very thin shape.Accordingly, as shown in FIG. 4, the present invention can use a thinsheet filter 14, which is rolled and placed in the rotary cylinder. Inorder for the filter to be rolled and placed in the rotary cylinder intight contact the inner wall of the cylinder, the filter may haveelasticity. Alternatively, a plurality of punching sheets made from thinstainless may be placed in an overlapped manner in the rotary cylinder.

When the filter should be removed, a flap 15 is made at the edge of thefilter. The flap 15 is pinched, and pulled while twisting the filter. Bydoing so, the diameter of the rolled filter becomes smaller and thisfacilitates the pulling out of the filter.

It should be noted that the mesh size of the filter at the filterentrance may be different from that at the filter exit. Also, a catalystmay be provided in the rolled filter.

INDUSTRIAL APPLICABILITY

The present invention provides an inexpensive, long-lasting, exhaust-gaspurification device with an enhanced capability with respect toparticulate removal because it can use a very thin and light-weightfilter and the filter hardly suffers from clogging.

1-2. (canceled)
 3. A rotary filter type particulate removing apparatuscomprising: a stationary cylinder; a rotary cylinder rotatably andcoaxially placed in the stationary cylinder, the rotary cylinder havinga cylindrical wall, the rotary cylinder having an extending portionwhich extends beyond the stationary cylinder; at least one vaneextending from the cylindrical wall of the rotary cylinder; a gas inletfor introducing a gas, which contains particulates, into a space betweenthe stationary cylinder and the rotary cylinder; a plurality of holesformed in the cylindrical wall of the rotary cylinder; an opening formedin a lower part of the stationary cylinder; a trap attached to the lowerpart of the stationary cylinder to cover the opening; a filter providedin the rotary cylinder such that the filter extends along an inner wallof the cylindrical wall of the rotary cylinder; and a fan attached tothe extending portion of the rotary cylinder.
 4. The rotary filter typeparticulate removing apparatus according to claim 3, further comprisinga motor attached to the stationary cylinder for rotating the rotarycylinder.
 5. The rotary filter type particulate removing apparatusaccording to claim 3, further comprising a cover for housing the fan. 6.The rotary filter type particulate removing apparatus according to claim3, wherein the vane includes a wire gauze.
 7. The rotary filter typeparticulate removing apparatus according to claim 3, wherein the vaneincludes a plate having a plurality of bores.
 8. The rotary filter typeparticulate removing apparatus according to claim 3, wherein the vaneincludes a brush.
 9. The rotary filter type particulate removingapparatus according to claim 3, wherein the filter is made from astainless steel.
 10. The rotary filter type particulate removingapparatus according to claim 3, further comprising a catalyst placed inthe rotary cylinder.
 11. The rotary filter type particulate removingapparatus according to claim 3, wherein the filter is made from a thinsheet material so that the filter is rolled in the rotary cylinder. 12.The rotary filter type particulate removing apparatus according to claim11, wherein the filter has elasticity so that an outwardly expandingforce is generated when the filter is rolled.